Melanoma

Description:

Melanoma – the malignant tumor of skin arising from melanocytes – the cells producing melanin.
Melanocytes have a neuroectodermal origin and are the closest to the cells which are taking part in formation of the peripheral sensitive device. The melanoma meets rather seldom (1,8 – 2,2 on 100 thousand population) and makes from 1 to 10% of all malignant tumors of skin. The tumor arises preferential at the age of 30-50 years; according to various statistical data it is noted or the identical frequency of defeat of men and women, or it is specified that women are ill more often than men.
Primary center of a melanoma can be located in the most various sites of an integument, and approximately at 2% of patients with melanoma metastasises primary center remains undetected.

Melanoma reasons:

The etiology of a melanoma of skin remains to the unknown, however there is a number of the factors to some extent influencing emergence or the course of a melanoma. So, in most cases the tumor arises from earlier existing nevus pigmentosus (approximately at 2/3 all patients). At some patients such transformation can be connected with an injury of a pigmental nevus, and also with hormonal changes in an organism (the puberty period, or, on the contrary, witherings of hormonal activity). In this regard it should be noted especially malignant course of a melanoma during pregnancy.
Studying of regional features of spread of malignant tumors demonstrated a role of solar radiation in developing of a melanoma of skin: an incidence index at the white population living in southern latitudes, above than at the local population possessing "pigmental antisolar protection".
Pretumor diseases for a melanoma is various pigmental nevus which is especially located on constantly injured places. A pigmental nevus is divided by a histologic structure on boundary (epidermal), vnutridermalny, mixed and blue nevus, and also "a juvenile melanoma". Development frequency on their background of malignant melanomas is various. The boundary nevus is most dangerous in this respect.
It is impossible to determine by outward a histologic kind of this or that nevus practically therefore it is necessary to be guided on their clinical versions. Distinguish a flat, papillary, knotty, warty and hairy nevus. It is noticed that a flat and knotty nevus regenerates more often, is more rare – hairy, papillomatous and warty. Very seldom the blue nevus regenerates. Clinically blue nevus is defined rather easily as the nevus is located deeply in a derma and between it and to surfaces the layer of the normal or thinned derma which causes coloring of a nevus (bluish-brown, bluish-gray and bluish) is available epidermis.
The juvenile melanoma in most cases is exposed to fibrous involution, but can sometimes be a source of malignant growth after puberty.

Melanoma symptoms:

Can be initial symptoms of transition of a benign pigmental tumor to malignant: 1) strengthening or easing (partial or full) pigmentation of a nevus; 2) its growth; 3) ulceration and bleeding of an ulcerated tumor; 4) nodulation or outgrowths on a nevus pigmentosus surface; 5) emergence of redness or a so-called congestive areola around the basis of primary center. Further there are pigmental and not pigmental radial growths which as if go from a pigmental new growth on the course of vascular or nerve pathways.
Emergence on intact skin slowly and furthermore quickly growing pigmented new growth it is always suspicious on a melanoma.
Insufficiently specific characters of malignant growth in rather early stages are temperature increase of a pigmental new growth on 0,7 C and more, and also ability of this tumor to accumulate radioactive phosphorus.
Unfortunately, sometimes primary center does not find clinical signs of growth: the pigmental nevus or other pigmental new growth externally does not change, then tumor dissimination signs are the first symptoms of the developed melanoma: increase in regional lymph nodes or emergence of pigmental new growths (satellites) around a nevus pigmentosus high-quality by sight or at the basis of pigmental "wart". Both these signs demonstrate lymphogenous spread of a tumor.
At further development of a melanoma in its basis there is a condensed infiltrate. The surface of a pigmental tumor can rise over skin level, and sometimes, on the contrary, ulcerates and in such cases the tumor can remind not healing ulcer. The surface of an ulcer can be lower than the level of skin that is most often noted at a pigment-free nevus. At exophytic and knotty forms of a melanoma the fungoid fungoid, polusharny or ploskobugristy tumor with uneven distribution and melanin inclusion, unequal on intensity, is gradually formed. Such tumor is easily injured, bleeds, ulcerates, however its surface can be smooth, as if "mirror". The consistence is moderately dense. Then there are single metastasises in lymph nodes, there can be also hematogenous metastasises. Innidiation at a melanoma has rough or even fulminant character more often, but sometimes maybe rather slow (from several weeks to several years). Many note the known recurrence in innidiation when emergence of metastasises is replaced by temporary stabilization, and then there is a new attack and generalization of process.
Innidiation at a melanoma is extremely variable and diverse. At a half of patients the "local" dissimination consisting in emergence of secondary metastatic nodes in skin is noted.
Hematogenous metastasises affect lungs, a liver, a brain, bones, adrenal glands, lymph nodes of the remote areas, etc. The remote metastasises in easy 968%) and in a liver (62%) are most frequent.

Diagnosis:

Approximately at 1/3 patients to make the clinical diagnosis of a melanoma very difficult, especially at a pigment-free kind of a tumor and when the disease is shown first of all by emergence of metastasises in this or that part of a body. Diagnosis of a melanoma is at a loss the fact that at it it is impossible to do a biopsy in usual workmanship (it is excluded exposition  and even puncture its options). The cytologic diagnostic method is acceptable only when the surface of a tumor is ulcerated and it is possible to take a print from an ulcerated surface, without injuring a tumor. Difficulties of diagnosis are caused by variety of clinical forms swelled up. So, the melanoma can sometimes have outward of the simple papilloma on the wide basis which is not pigmented, slowly growing and not disturbing the patient. Only for cosmetic reasons similar tumors can be removed in the surgical way, and not radical intervention leads to bystry dissimination or a recurrent tumor.
It is difficult to diagnose also small tumors which can have the most various appearance wide, flat, irregular shape, the roundish or oval educations appearing without visible injury or after it. Similar tumors can be taken for high-quality neurofibromas.

Treatment of the Melanoma:

Treatment of a melanoma has to be planned and be carried out depending on extent of distribution of tumoral process. The most widespread method of treatment of this malignant new growth is combined. There are methods of medicinal treatment including different types of regional chemotherapy, especially a perfusion method.
At the combined treatment method the first stage includes a short-distance roentgenotherapy. The single dose is recommended within 300-500 Rubles. As an optimum  total dose it is possible to recognize 10 000 – 12 000 R. Odnim from conditions of radiation inclusion in a zone of radiation of the fabrics surrounding a tumor to 3 cm from its edge is. Complex therapy includes: radiation of primary tumor (and regional metastasises if it is) against the background of intravenous administration of antineoplastic antibiotics; surgical oncotomy.
The second stage of the combined treatment of a melanoma of skin has to include: surgical (whether knife electrosurgical) excision of a tumor; along with primary center or 2-3 weeks later excise lymph nodes of zones of regional innidiation ("medical" if there metastasises clinically are defined, or "preventive" if they it is not palpated).
In general the forecast at a melanoma adverse, 5 years' survival at patients without regional metastasises with histologically the verified diagnosis seldom exceeds 40%, and in the presence of regional metastasises – 10-15%.